Envelope manufacture

ABSTRACT

Means for and method of producing envelopes from preformed envelop blanks in which these blanks are passed in closely spaced overlapping or shingled relation between closely spaced and opposed gum boxes which simultaneously apply ribbons of latex or adhesive to an exposed area at an end of the inner and outer surfaces of the envelop blanks forming at one end a sealing flap and at the other end an auxiliary sealing flap which, when folded with the latex on these flaps aligned and engaged in pressure contact, seals the envelope. These blanks after passing between the opposed gum boxes for simultaneous applications of the ribbons of latex, are then fed between heating chambers or zones for drying, and, subsequently scored and folded to provide an upper sealing flap and a reversely folded auxiliary sealing flap.

United States Patent 3,460,444 8/1969 Winkler etal.

ABSTRACT: Means for and method of producing envelopes from preformed envelop blanks in which these blanks are passed in closely spaced overlapping or shingled relation between closely spaced and opposed gum boxes which simultaneously apply ribbons of latex or adhesive to an exposed area at an end of the inner and outer surfaces of the envelop blanks forming at one end a sealing flap and at the other end an auxiliary sealing flap which, when folded with the latex on these flaps aligned and engaged in pressure contact, seals the envelope. These blanks after passing between the opposed gum boxes for simultaneous applications of the ribbons of latex, are then fed between heating chambers or zones for drying, and, subsequently scored and folded to provide an upper sealing flap and a reversely folded auxiliary sealing flap.

ENVELOPE MANUFACTURE The present invention relates to the production of envelopes from preformed envelope blanks which, when folded, include a back portion with a reverse or auxiliary sealing flap, side flaps, and a front portion with a sealing flap, the reverse fold end flap covering the adhesive until folded back to expose its gummed areafor contact by the aligned gummed area of the sealing flap and, when these gummed flaps are pressed together in pressure contact, the envelope is pressure sealed.

Among the objects of the present invention is the provision of novel means for and method of simultaneously applying ribbons of latex to scaling areas at opposite ends of an envelope blank, the blank when subsequently scored and folded to complete the envelope, being provided with two gummed sealing flaps to be adhesively joined when in pressure contact and the envelope is sealed for use.

The envelope blanks when fed to and between opposed gum boxes are disposed in closely spaced, overlapping or shingled relation with the spacing therebetween being only sufficient (usually approximately one-half inch) to expose areas whereby ribbons of gum or latex are continuously wiped onto the reverse exposed edges at the opposite ends of the blanks and forming the reverse or auxiliary sealing flap or fold at one end and the sealing flap at the other end of successive blanks, the sealing flap having a continuous ribbon of latex applied thereto and the reverse end or auxiliary flap at the back of the formed envelope having an interrupted ribbon of latex, these adhering surfaces when brought into pressure contact effectively sealing envelope in use without the necessity of moistening.

The successive envelope blanks in closely spaced overlapping relation are fed between the adjacent gumming boxes for applying ribbons of an adhesive such as latex to the opposite sealing flaps at the upper and lower surfaces of the blanks, and then feeding these blanks through upper and lower drying chambers for drying the applied latex and preventing the sealing flaps and adjacent gummed envelope blanks from adhering. In the feeding and drying operation the closely spaced and overlapping gummed envelope blanks are carried by conveyor belts or chains and passed through the upper and lower drying chambers with the gummed areas directly exposed to the heat in the drying chambers for a period of time and temperature sufficient to effect adequate drying before scoring and folding to complete the resulting envelopes.

Due to the overlapping blanks being disposed in closely spaced overlapping relation, only the upper and lower areas to which the adhesive is applied, are exposed permitting the continuous application of latex to these exposed areas which when subsequently scored and folded provide the sealing flaps.

Thus the present invention provides a novel means for and manner of simultaneously applying ribbons of latex to areas at the opposite sides of envelope blanks, one area being on the reverse fold end sealing flap on the body portion and the other area being on the sealing flap and so related that these gummed areas when brought into contacting engagement will self-adhere and provide an effective seal.

in the drying operation, the closely spaced, overlapping blanks after being simultaneously gummed on an exposed upper and lower area of the opposite sides, are carried by conveying means such as by belts or by chains having gripping fingers for moving the gummed blanks in overlapping relation through the drying chambers and, after drying, each blank is scored, the end flaps folded, gum applied to the outer surfaces of the side flaps, after which the bottom flap is folded and adhered to side flaps, the auxiliary or bottom seal flap being reversely folded to cover its ribbon of latex and the top end or sealing flap folded onto the formed envelope to cover and protect its sealing latex against adherence with the auxiliary sealing flap.

Further objects are to provide a construction of maximum simplicity, efficiency, economy and ease of assembly, and such furtherobjects, advantages and capabilities as will later 'more fully appear and are inherently possessed thereby.

In the drawings:

FIG. I is a diagrammatic view of the means and manner of producing envelopes from envelope blanks and showing an envelope blank in its various stages of scoring and folding to complete the envelope.

FIG. 2 is a plan view of the outer side of an envelope blank after the latex has been applied.

FIG. 3 is a plan view of the inner side of an cnvclopc blank after the latex has been applied to this side.

FIG. 4 is a fragmentary view in end elevation of the gum boxes for simultaneously applying ribbons of latex to the opposite sides of successive envelope blanks.

FIG. 5 is a view in front elevation of the outer gum box, the view being taken on the line 5-5 of FIG. 4.

Referring to the disclosure in the drawings, the present invention relates to a novel means and manner for applying a self-adhering adhesive such as latex to envelope blanks l0 fed from a suitable feeding mechanism onto spaced vacuum feed belts 11 and 12 over drums l3 and 14 carrying successive blanks in closely spaced, overlapping relation on and delivering these blanks between closely spaced inner and outer gum boxes 15 and 16 for flowing ribbons of the latex or adhesive onto predetermined areas on the inner and outer surface of each blank at the lower and upper ends.

The inner gum box 15 provides a reservoir for supplying a continuous ribbon of latex or adhesive 17 fed through a continuous transverse slot 18 onto an end forming the sealing flap 19 of the envelope 20 and the outer gum box 16 supplies spaced or interrupted ribbons 21 of latex or gum through interrupted transverse slots 22 onto an end or auxiliary sealing flap 23 of the envelope and at the opposite end and opposite side of the blank from the sealing flap 19, the continuous slot 18 and the adjacent interrupted slots 22 extending substantially across the width of the gum boxes 15 and 16. Each slot 18 and 22 is approximately one sixty-fourth inch in cross section and disposed in the lower curved end of the inclined front wall 24 of each box above the bottom wall or base 25, with each box including sidewalls 26 and 27, and a rear or end wall 28 providing a reservoir from which the latex or adhesive flows through the slots 18 and 22 onto the sealing areas of the sealing flaps l9 and 23. Each box is mounted upon a support or bracket 29 tiltably and adjustably mounted upon a transverse axis 31 for inclining the box and adjusting the flow of the latex orgum from the slots.

Each envelope blank 10 is fed and retained on the vacuum belts ll and 12 and drums l3 and- 14 and passes between the inner and outer gum boxes 15 and 16 to receive simultaneously on both sides of each blank the desired ribbons of latex after which the gummed blank 10 is carried by the vacuum belts between spaced upper and lower heating units 32 and 33 to dry the latex before the blanks are fed by the belts or conventional chain drive to subsequent conventional mechanism for scoring and folding, including scoring blades 34 for providing the longitudinal score or fold lines at 35 and 36, and scoring blades 37 for providing the transverse score or fold lines at 38, 39 and 41. The score lines 35 and 36 provide side flaps 42 and43 and the transverse score line 41 provides an end or sealing flap 19 to which has been affixed the continuous strip 17 of latex, and the score lines 39 and 38 a rear body portion or flap 45 with the connected end or auxiliary sealing flap 23 to the undersurface of which has been affixed the spaced strips 21 of latex.

The end or auxiliary sealing flap 23 is reversely folded and the side flaps 42 and 43 are folded inwardly and down upon the front body portion 47 of the blank as by conventional means such as plow shares at 48. Next a portion of the side flaps or tabs 42 and 43 are gummed at 30 and the body flap or portion 45 providing the rear of the envelope is folded inwardly and downwardly onto the inwardly folded side flaps or tabs 42 and 43'. Gum for affixing the rear body portions 45 to the side flaps 42 and 43 is applied to the folded side flapswhereby when the rear body port-ion is folded thereon, they are adhesively joined together by pressure applied by rolls at 49, and the auxiliary sealing flap 23 is reversely folded to cover and protect the latex strips or ribbons 21'. Also the sealing flap 19 may be folded to protect its latex ribbon 17', afte'r which the completed envelopes 20 are delivered and stacked at 50.

it is to be understood that the envelope blanks to which the latex or adhesive is applied are passed between the gum boxes in closely spaced overlapping or sliii'igled relationwhereby the ribbons of latex applied to the opposite sides of the envelope blanks are simultaneously and continuously affixed to the areas providing the sealing tabs insttccessive envelopes.

Although the disclosure refers to the application of ribbons of latex which when brought into pressure sealing contact, provide for effectively sealing the mapsof the envelopes, the present invention is applicable to envelopes in which ribbons of a moistening type of gum may be applied rather than latex.

I claim:

1. In the manufacture of envelopes from envelope blanks having a sealing flap at one end an'd an' opposite auxiliary sealing flap at the other end for press'nresealing contact, means feeding and conveying the blanks in overlapping relation in cludingvacuum' belts and drums and closely adjacent inner and outer gum boxes for simultaneously applying ribbons of latex to the opposite sides of each blank in areas to subsequently provide a sealing flap and a reversely folded auxiliary sealing flap, the inner of said gum boxes having a continuous narrow transverse slot through which a ribbon of latex flows onto one sealing flap of the blank and the outer gum box has'interrnpted transverse slots through which divided ribbons of latex flow onto the other sealing flap at the opposite side of the blank, each gum box has an inclined front wall terminating at its lower end in a curved surface containing the slots, each box being mounted on a til'table support for inclining and ad justing the position of said gum boxes and the relative location of their slots for controlling the flow through said slots, and means for drying the latex on the opposite sides of the blanks.

2. in the manufacture of envelopes as set forth in claim 1, and means for subsequently scoring and folding the envelope blanks to provide side and sealing flaps after drying of the latex including reversely folding the auxiliary sealing flap for protecting the latex applied thereto prior to use of the assem bled'envelope. 

1. In the manufacture of envelopes from envelope blanks having a sealing flap at one end and an opposite auxiliary sealing flap at the other end for pressure-sealing contact, means feeding and conveying the blanks in overlapping relation including vacuum belts and drums and closely adjacent inner and outer gum boxes for simultaneously applying ribbons of latex to the opposite sides of each blank in areas to subsequently provide a sealing flap and a reversely folded auxiliary sealing flap, the inner of said gum boxes having a continuous narrow transverse slot through which a ribbon of latex flows onto one sealing flap of the blank and the outer gum box has interrupted transverse slots through which divided ribbons of latex flow onto the other sealing flap at the opposite side of the blank, each gum box has an inclined front wall terminating at its lower end in a curved surface containing the slots, each box being mounted on a tiltable support for inclining and adjusting the position of said gum boxes and the relative location of their slots for controlling the flow through said slots, and means for drying the latex on the opposite sides of the blanks.
 2. In the manufacture of envelopes as set forth in claim 1, and means for subsequently scoring and folding the envelope blanks to provide side and sealing flaps after drying of the latex including reversely folding the auxiliary sealing flap for protecting the latex applied thereto prior to use of the assembled envelope. 